Pack opening apparatus and method

ABSTRACT

An apparatus for packing products includes a product information acquisition stage arranged to acquire information relating to one or more characteristics of products on a product packing line; a bag supply system arranged to supply bags sequentially as individual products on a conveyor approach a packing apparatus; and a bag opener arranged to automatedly take up a bag from the bag supply system as each individual product approaches the bag opener, and to subsequently machine open a mouth of each bag to a controlled extent based on information relating to products being packed acquired at the upstream product information acquisition stage. An apparatus for packing products includes a product information acquisition stage arranged to acquire information relating to one or more characteristics of products on a product packing line; a product packing stage; and two or more generally parallel conveyors arranged to deliver products of different sizes to the packing stage.

The present application is a 35 USC § 371 application of PCT/NZ02/00290filed Dec. 20, 2002 which claims the benefit of New Zealand PatentApplication No. 516329 filed Dec. 21, 2001 and New Zealand PatentApplication No. 516330 filed Dec. 21, 2001.

FIELD OF THE INVENTION

The invention relates to the packing of products in flexible packagingand in particular bags or similar formed from a plastics material, andto the packing of irregularly sized products such as meat cuts in bagsor similar.

BACKGROUND OF THE INVENTION

Typically in a meat processing plant carcasses are butchered to primalmeat cuts which are then individually packed, typically in bags manuallyby operators on a packing line. The meat cuts on a conveyor willtypically vary significantly in size.

In other applications there may be a need to bag products of varyingsize, or varying numbers of products per bag.

SUMMARY OF THE INVENTION

In a first aspect, an apparatus for packing products comprises: aproduct information acquisition stage arranged to acquire informationrelating to at least one of the height, width, length, volume, and shapeof individual products on a product packing line; a bag supply systemarranged to supply bags sequentially as individual products on aconveyor approach a packing apparatus; and a bag opener arranged toautomatedly take up a bag from the bag supply system as each individualproduct approaches the bag opener, and to subsequently machine open amouth of each bag to a variable extent of lift in a direction atapproximately right angles to a major plane of the unopened bag and to avariable degree of width opening in a direction approximately in a majorplane of the unopened bag, based on information relating at least one ofthe height, width, length, volume, shape, and weight of the productacquired at the product information acquisition stage.

In a second aspect, a method for packing products comprises: at anupstream product information acquisition stage, acquiring informationrelating to at least one of the height, width, length, volume, or shapeof individual products on a product packing line; machine supplying bagssequentially as individual products on a conveyor approach a packingapparatus; and automatedly taking up on an automated bag opener a bagfrom the bag supply system as each individual product approaches the bagopener, and machine opening a mouth of the bag to a variable extent oflift in a direction at approximately right angles to a major plane ofthe unopened bag and to a variable degree of width opening in adirection approximately in a major plane of the unopened bag, based oninformation relating to at least one of the height, width, length,volume, shape, and weight of the product acquired at the upstreamproduct information acquisition stage.

In a third aspect, a method for packing products comprises:

acquiring information relating to at least one of the height, width,length, volume, shape, and weight of products on a product packagingline,

machine opening the mouth of each bag to a controlled extent based oninformation relating at least one of the height, width, length, volume,shape, and weight of the products being packed acquired at an upstreamproduct information acquisition stage, and

delivering or loading products into bags and into a vacuum packagingmachine via two or more generally parallel load conveyors.

In a fourth aspect, a method for packing products comprises: acquiringinformation relating to at least one of the height, width, length,volume, shape, and weight of products on a product packing line, anddelivering or loading products into bags and into a vacuum packagingmachine via two or more generally parallel load conveyors.

In a fifth aspect, an apparatus for packing products comprises: aproduct information acquisition stage arranged to acquire informationrelating to at least one of the height, width, length, volume, and shapeof products on a product packing line; a product packing stage; and twoor more generally parallel conveyors arranged to deliver products ofdifferent sizes to the packing stage.

In a sixth aspect, a method for packing products comprises: acquiringinformation relating to one or more characteristics of products on aproduct packing line; and delivering products of different sizes to aproduct packing stage, via two or more generally parallel conveyors.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is further described with reference to the accompanyingfigures by way of example, wherein:

FIG. 1 is a schematic view of the overall layout of one embodiment ofbagging apparatus;

FIG. 2 is a schematic view of one embodiment of a bag opener;

FIG. 3 is a schematic view of another embodiment of a bag opener;

FIG. 4 is a schematic view of another embodiment of a bag opener;

FIGS. 5A to 5E show steps in the operation of the bag opener of FIG. 4;

FIGS. 6 to 13 schematically show steps in the operation of anotherembodiment of a bag opener and a product loading system;

FIGS. 14 to 17 schematically show a plan view of the layout andoperation of another embodiment of a product loading conveyor system;

FIG. 18 shows a detailed plan view of a product loading conveyor system;and

FIG. 19 shows the product loading conveyor system of FIG. 18 in thedirection of arrow Y of FIG. 18.

DETAILED DESCRIPTION OF THE INVENTION

Typically the bags will be plastic bags or sacks. Typically the bagswill be sealed at one end and unsealed at the other. The bags aresupplied to the packing apparatus sequentially, as individual productssuch as meat cuts approach, from a bulk supply such as a stack or rolledstock of bags for example, or alternatively may be made on-line to astandard length, or to the appropriate length tailored to the size ofindividual meat cuts, by cutting and sealing bags from tube stock forexample.

The bag opening means will typically comprise one or more parts whichinsert into the mouth of each bag and spread the bag to a controlledextent of opening. Fingers inserted into the bag can open the bag to avariable extent of lift (the height direction, at approximately rightangles to the plane of the unopened bag) combined with a variable degreeof width opening, controlled dependent on product size. Alternativelymeans may grip the bag mouth from the exterior for controlled opening ofthe bag, rather than inserting into the interior of the mouth of thebag.

Information from the product information acquisition stage on productcharacteristics such as size can be used to deliver or load products byactivating selected conveyors for the products. For example in a simpleform two parallel conveyors may be provided, one of which delivers orloads smaller products and both of which are activated to run inparallel to deliver or load larger products. The two conveyors may havesimilar or different widths. In another form three or more parallelconveyors may deliver and load products. The conveyors may be “centered”i.e. a center conveyor may be flanked on either side by adjacentconveyors of a similar width which may be smaller or larger in widththan the center conveyor, or may be non-centered.

In one embodiment the conveyors can be arranged to load products intothe bags by telescoping or moving forward into the bags to an extentdependent upon the size of the product i.e. further for longer productsthan for shorter products, based on product size information previouslyacquired at the upstream product information acquisition stage.

The acquired information relating to the individual products such asindividual meat cuts may include any one of dimensional information suchas height information, width information, or height, width and lengthinformation, volume or shape information, or weight information, or acombination of one or more of any such information.

Referring to FIG. 1, the packing apparatus of the invention comprises aproduct information acquisition stage 1 which may be a machine visionsystem beneath which individual products such as meat cuts M pass alongconveyor 2. The machine vision system acquires information relating toone or more characteristics of the individual products such as meat cutspassing through the product information acquisition stage 1 on conveyor2. As a minimum the product information acquisition stage 1 may acquiresimple dimensional information relating to the individual products suchas a combination of height and width, or height, width, and lengthinformation, or other dimensional information indicative of the size ofthe meat cuts or the volume or shape of the meat cuts. Weightinformation may supplement dimensional information acquired by themachine vision stage.

A product information acquisition stage 1 may comprise a digital camerasystem which “sees” individual meat cuts and/or a system which directsat least one beam or line from a scanning laser over individual meatcuts with deflection and/or reflection of laser light on the meat cutbeing seen by a camera system, and the resulting information beingprocessed to provide the dimensional and/or volume or shape informationin relation to each meat cut. Alternatively the product informationacquisition stage may simply be a series of horizontal and verticalbeams across the conveyor path at different heights or spacings throughwhich the meat cuts pass, providing information to a control system asto the width and height and optionally length of the meat cuts based onthe number of beams broken by each passing meat cut. Any other productinformation acquisition stage which enables the acquisition ofinformation as to product length, width, size, volume, shape or similarmay be used.

The acquired information may be supplied directly to individualelectronic or programmed controllers for one or more bag openers, or toa common control system for a packing line which also controls otherstages of the packing line, and synchronises the arrival of individualproducts at the bag opening stage. The acquired information can be usedso that individual bags are opened to an extent which matches eachindividual product.

FIG. 2 shows one form of bag openers which comprises parts such asfingers 5 which in operation of the packing apparatus insert into themouth of each bag such as those indicated at B, and move apart to openthe bag mouth to a controlled degree of height or lift. Similar parts orfingers (not shown in FIG. 2) may move in a lateral or width-wisedirection to open the bag to a fixed or controlled degree of lateralopening. The degree of lift may be continuously variable dependent uponthe size of the individual product or may be stepped between a number ofpredetermined levels of opening for products within broad size ranges.For each such a size the bag may be opened or spread laterally to acontrolled degree of width which may be continuously variable dependenton product size, or to fixed steps of width opening. The lift openingfingers and width opening fingers may be controlled by servo motorswhich adjust the position of the lift and width opening of fingers foreach bag, or by small pneumatic cylinders, or by any other suitablemechanical arrangement. The lift and width opening fingers may bemounted for vertical and horizontal movement on peripheral entry frame 6as shown, or by any other suitable arrangement.

Typically products such as meat cut M in FIG. 2 will approach the bagopener on a conveyor such as conveyor 7 for example. In the bag openerof FIG. 2 the entry frame 6 carrying the spreader fingers is pivotallymounted at 8 so that it can pivot between the upper position shown inhard outline and the lower position shown in phantom outline. Prior toor as each product approaches, the spreader fingers enter the mouth ofand pick up a fresh bag, and the entry frame 6 pivots upwardly (from theposition shown in phantom outline to the position shown in hardoutline). The spreader fingers are driven apart to open the bag to acontrolled extent, based on information provided from the earliermachine vision or similar product information acquisition stage throughwhich the product has passed. The open bag is thus presented to theproduct which is conveyed to the open bag, which is then caught by exitconveyor 9 which carries the bagged product onward, pulling the mouth ofthe bag from the spreader fingers 5. In FIG. 2 different degrees ofopening of the bag mouth are shown in phantom outline at differentpositions of the spreader fingers 5.

The apparatus showing in FIG. 3 is similar in operation to that shown inFIG. 2 except that the bags are brought down into the product flow fromabove, rather than from below as in the apparatus of FIG. 2. In FIG. 3the same reference numbers indicate the same components as in FIG. 2.Entry frame 6 carries lift and width opening fingers in a similararrangement to the apparatus of FIG. 2. The entry frame 6 is mounted soas to pivotally move in the direction of arrow C from position 10 atwhich the spreader fingers enter the mouth of and pick up a fresh bag,to the lower position as shown. Prior to or during downward movement thespreader fingers 5 are driven apart to open the bag to a controlledextent, based on information provided from the earlier machine vision orsimilar product information acquisition stage through which the producthas passed. Conveyor 7 has a telescoping forward end 7 a which deliversthe product through the entry frame 6 and into the open bag as the bagis brought down towards the telescoping conveyor end 7 a extending overthe exit conveyer 9, so that the product is entered into the bag and thebag is drawn over the product. The conveyor end 7 a then withdrawsleaving the product in the bag which is then caught by exit conveyor 9which carries the bagged product onward, pulling the mouth of the bagfrom the spreader fingers 5, following which the entry frame returns topick up a fresh bag from position 10.

In the embodiments of FIGS. 2 and 3 the product items move towards thebag which is stationary or relatively stationary. In an alternativearrangement however the open bags may be moved towards and/or drawn overthe stationary or relatively stationary product item. It is alsopossible that as the product items move, the open bag may be moved to bedrawn over the moving product item, so that the bag and product itemsuch as meat cuts are moving towards each other as the product isentered into the bag.

A control system may synchronize the arrival of individual meat cutswith the acquired information relating to the individual meat cuts.Alternatively the product information acquisition stage and baggingstation may be autonomous, and where bags are opened according toproduct weight and for example a weighing conveyor may be positionedimmediately upstream of the bagging stage. In another arrangementacquired information relating to each product may be sent directly fromthe product information acquisition stage to the packing station andretained in a database at the packing station until that meat cut hasarrived, and is then used to open the bag to the appropriate extent forthat size of product. In a yet more sophisticated arrangement individualmeat cuts may be tracked along a packing line so that the system candetect if any individual meat cut is removed from the product stream forany reason, to avoid mis-indexing of the meat cuts and bags, and thismay be achieved by detecting and tracking the movement of each meat cutfrom one conveyor to the next.

In the embodiments of FIGS. 2 and 3 the spreader fingers moveheight-wise (lift) and width-wise to open the mouth of the bag to arectangular or square shape. This is not essential and the spreaderfingers or equivalent may be positioned to open the mouth of the bag toa non-regular shape more adapted to the shape of the productdynamically, as the product is loaded. A further possibility is that thespreader fingers or equivalent may be dynamically opened and closed asthe product enters the bag. For example for a hump back-shaped productsuch as a typical meat cut, the fingers may open the bag to a controlleddegree and then as the product is entered into the bag continue openingthe bag as the highest part of the product passes through the bagopening, and then begin to close the bag as the trailing portion of theproduct enters the bag, and optionally near-fully or partially close thebag. For this purpose the spreader fingers may grip the periphery of thebag mouth. For example a 3D image of the product may be acquired at theproduct information acquisition stage and a multiple number of spreaderfingers moved to duplicate the shape of the product, and open the bag tothe shape of the product, as the product is loaded. Other similarvariations are possible.

As indicated previously, bags may be supplied from a stack or rolledstock or alternatively may be made on-line by cutting and sealing bagsfrom tubes, preferably to a length for each bag tailored to the size ofindividual products. A range of bag or stock widths may be available ina range of materials such as oxygen barrier materials, export gradepacking material, and so forth from which the bags may be selected asdirected by the control system. Bags preprinted with different labellingor branding information may also be provided and selected from.

Another embodiment of the bag opener and its operation are shown inFIGS. 4 and 5A to 5E. The bag opener comprises four parts hereinreferred to as blades 70 and 71. The lower blades 70 are carried bymounts 72 which slidably move on shafts 73, and upper blades 71 arecarried by mounts 74 fixed to the shaft 73. Pneumatic cylinder 75 canmove the lower blades 70 vertically in the direction of arrow W in FIGS.4 and 5. The mounts 72 carrying the lower blades 70 are connected byshaft 76 to which the shaft 77 of the pneumatic cylinder 75 is coupled.FIG. 5C (which does not show the operating cylinder 75) shows the lowerblades 70 separated from the upper blades 71, and in the lowermostposition of the lower blades 70. FIGS. 5A and 5B show the lower blades70 in their upper most position. The lower and upper blade pair 70 and71 on one side and the lower and upper blade pair 70 and 71 on the otherside of the bag opener can be moved widthwise relative to one another inthe direction of arrow Z in FIGS. 4 and 5 as shown. Referring to FIG. 4,the shafts 73 are in turn carried by left and right carriages 78 whichare movably mounted on subframe 79. Subframe 79 also carries threeoperating cylinders 80 each having a different stroke length, on commonshaft 81. The three cylinders together provide eight programmablewidthwise positions in the direction of arrow W between the lower andupper blade pairs 70 and 71 on either side. In an alternative form theremay be four cylinders which may provide for sixteen programmable widthpositions, or the cylinders may be replaced by a single variable strokepneumatic or hydraulic cylinder, or in this or other bag openersdescribed herein the cylinders 75 and 80 may be replaced by for examplerack and pinion drive systems. FIGS. 5D and 5E schematically show arange of relative positions to which the blades 70 and 71 may be movedrelative to one another. FIG. 5D shows how the bag opener may open themouth of a bag of a particular width e.g. a 200 mm width plastic bag, toa range of mouth open shapes, between a maximum width-minimum heightposition, and a maximum height-minimum width position of the blades.FIG. 5E shows a similar range of positions to which the mouth of alarger bag e.g. in 300 mm width bag, may be opened by the bag opener.

Referring to FIGS. 5A and 5B, to initially separate the two sides of themouth of a bag enabling the bag opener blades 70 and 71 to insert intothe mouth of the bag, suction cups 82 may be provided above and belowthe bag mouth which may operate to grip either side of a bag andinitially separate the two sides of the bag mouth, enabling the blades70 and 71 of the bag opener to enter into the mouth of the bag. In FIG.5A a bag is schematically indicated at B, held by suction cups while theblades 70 and 71 in their minimum width minimum height position insertinto the mouth of the bag. Subsequently the left and right blade pair 70and 71 may move apart widthwise, while the suction cups are released, torelease the bag from the suction cups. The suction cups then move fullyaway from the bag or the bag opener blades carrying the bag may pivotaround shaft 83 (see FIGS. 5A to 5C) to move the bag opener carrying thebag away from the suction cups, and the bag opener blades may then moveto one of the positions shown in FIG. 5D or 5E to open the bag to enableloading into the bag of the product to be packed, or bringing of the bagover the product to be packed.

Another embodiment of a bag opener and product loading system and itsoperation is shown in FIGS. 6 to 13. In use meat cuts such as thatindicated at M are carried by product supply conveyor 20. Meat cuts aredelivered by the product supply conveyor 20 onto elevator plate 21 whenit is in its lowered position as shown in FIG. 6, and are then elevatedas shown in FIGS. 7 and 8. Movement of the elevator plate 21 is drivenby hydraulic cylinder 22, which is in turn carried by a moving carriageassembly 23 which moves in the direction of arrow J in FIG. 6 on themachine bed 24. For example, the moving carriage assembly 23 may bemoveably mounted to the machine bed 24 by wheels 25, and driven byhydraulic cylinder 26. When the product supply conveyor 20 has deliveredthe product onto the elevator plate 21, the forward telescoping end ofthe conveyor 20 withdraws.

An empty bag such as bag B is picked up from a bulk supply as will befurther described, the two sides of the bag mouth are separated, and thebag is brought down from the position shown in FIG. 6 to the positionshown in FIG. 7 by pivoting bag pickup arm 27 which moves in thedirection of arrow F in FIG. 6. The bag pickup arm 27 in its upperposition shown in FIG. 6 picks up a fresh bag and then pivots down whileat the same time arm 28 forming part of a bag opener and bag openercarrying bag opening means in the form of figures or spoon plates 29moves upwardly to the position of FIG. 7. The partially open mouth ofbag B is entered onto the fingers 29 of bag 28 as shown. The bag openerarm 28 having received a bag then pivots downwardly as shown in FIG. 8.As it does so the fingers 29 are driven apart to open the mouth of thebag further, e.g. to a desired extent to match the size of theapproaching meat cut M, as will be further described. Movement of thebag opener arm 28 and the elevator plate 21 is coordinated so that themeat cut is presented to the bag opener arm 28 as it pivots downwardlyas shown in FIG. 8, and in doing so enters the open mouth of the bagover the meat cut on the elevator plate as shown in FIG. 9.

The carriage assembly 23 is then moved forward (by cylinder 26) to theposition shown in FIG. 10 to carry the meat cut in the open mouth of thebag on the elevator plate, onto the conveyor as shown. At about the sametime product ejector carriage 30 is moved forward as indicated by arrowK in FIG. 6. The product ejector carriage 30 is movably mounted in themachine bed 24 and may be driven by hydraulic cylinder 31 for example.The product ejector carriage carries ejector plate 32 which moves in thedirection of arrow I in FIG. 6 relative to the product ejector carriage30, and may be driven by a cylinder 33 carried by the product ejectorcarriage 30. Referring to FIG. 11 cylinder 33 is then actuated to movethe ejector plate 32 forward to push the meat cut further into the bag,following which the ejector plate 32 withdraws, and product ejectorcarriage 30 moves back—see FIG. 12—while at about the same time thefingers 29 of the bag opener arm 28 close together and then withdraw. Atabout the same time or prior the product supply conveyor 30 operates tomove the next meat cut onto the elevator plate 21 ready to load the nextmeat cut into a bag and into the next vacuum chamber in the same way.

The elevator plate 21 in the particular arrangement described lifts theproducts to the bag opener but an alternative arrangement may omit theelevator plate 21 and related parts and a product conveyor such as theproduct conveyor 20 may deliver the products directly to the bag opener.

As referred to above the bag opener arm 28 includes fingers orplate-like spoons 29 which insert between the separated sides of themouth of a bag, and then move apart to open the bag mouth, preferably toa controlled degree of height or lift. Optionally similar fingers may beprovided on either side which move in a lateral or width-wise directionto open the bag to a fixed or controlled degree of width opening. Thedegree of lift may be continuously variable dependent upon the size ofeach individual product or may be stepped between a number ofpredetermined levels of opening for products within broad size ranges.For each such a size the bag may be opened or spread laterally to acontrolled degree which may be continuously variable dependent onproduct size, or to fixed steps of lateral opening. The lift openingfingers and optionally width opening fingers may be controlled by servomotors which adjust the position of the lift and lateral opening offingers for each bag, by small pneumatic cylinders, or by any othersuitable mechanical arrangement. The extent to which the spreaderfingers 29 are driven apart to open the bag to a controlled extent isbased on information provided from an earlier machine vision or similarproduct information acquisition stage through which each product passes.

A control system may control operation of the machine as describedabove, and may also synchronize the arrival of individual meat cuts withthe acquired information relating to the individual meat cuts. Inanother arrangement acquired information relating to each product may besent directly from a product information acquisition stage to thepacking and vacuuming station and retained in a database at the packingand vacuuming station until that meat cut has arrived, and is then usedto open the bag to the appropriate extent for that size of product.Alternatively, individual meat cuts may be tracked along a packing lineso that the system can detect if any individual meat cut is removed fromthe product stream for any reason, to avoid mis-indexing of the meatcuts and bags, and this may be achieved by detecting and tracking themovement of each meat cut from one conveyor to the next.

Bags may be supplied from a stack or rolled stock or alternatively maybe made on-line by cutting and sealing bags from tubes. A range of bagor stock widths may be available in a range of materials such as oxygenbarrier materials, export grade packing material, and so forth fromwhich the bags may be selected as directed by the control system. Bagspreprinted with different labelling or branding information may also beprovided and selected from. Referring to FIG. 6, in one embodiment bagsmay be supplied from bag magazines 40, each of which contains rolls ofprefabricated bags of different sizes and/or types of bags with variousproperties e.g. different oxygen barrier or puncture properties orprinted labelling information. Alternatively one or more of the bagmagazines 40 may be replaced by one or more on line bag making machines(as are known in the art). As each meat cut approaches or is beingloaded, the machine control system causes one of the bag magazines topresent a bag to bag delivery conveyor 41, of the appropriate sizeand/or type for the particular meat cut. Bag delivery conveyor 41 passesaround rollers 42, and picks up the bag from the selected bag magazine40 and delivers it closed mouth first to the position of bag B in FIG. 6ready for pick up by the bag pickup arm 27. The bags may pass belowprinter 43 and have information printed on the bag relating for exampleto the specific meat cut to be packaged e.g. weight or type informationwhere the bags have already been pre-printed with more genericinformation such as branding information for example. To separate thetwo sides of the mouth of the bag ready for pick up by the bag pick uparm 27, one or more suction cups above and below the bag mouth may gripeither side of the waiting bag and then move slightly apart to separatethe two sides of the bag mouth. A series of suction cups or alongitudinally extending suction bar may be provided above and below thebag mouth. The control system moves the suction cups towards the bagmouth on either side and applies suction at the appropriate time, andreleases the suction when the bag has been picked up by the bag pickuparm 27, to allow the bag pickup arm 27 to pivot downwardly to enter thebag mouth onto the fingers 29 of the bag opener arm 28. Alternativearrangements for initially separating the bag mouth may be used however.

FIGS. 14 to 17 show in plan view the layout and operation of anotherembodiment of a product loading conveyor system. Such a product loadingconveyor system may be used as the conveyor 7 which delivers products tothe bag openers of FIG. 2, 3 or 4 for example, or as the productconveyor 20 or equivalent which delivers products to the bag opener ofFIGS. 6 to 13.

Referring to FIGS. 14 to 17, products of different sizes such as meatcuts M are loaded at a packing station 50 on parallel spaced conveyors51. The meat cuts after packaging are carried away from packing station50 on exit conveyor 52.

Any one or more of the two or more conveyors 51 may be activated by acontrol system, dependent on the product size. For example when smallermeat cuts are identified by the product information acquisition stagethey are directed to a center conveyor and only the center conveyor isactivated, as shown in FIG. 14. A bag opener (not shown in FIGS. 14 to17) 50 may present a smaller bag or a bag which is opened to a lesserextent, into which the smaller meat cut M on the center conveyor isdelivered. The packing station may align the bags with the centerconveyor. When the machine vision system identifies a meat cut ofintermediate size such as indicated at M in FIG. 15, more of the inputconveyors 50 are activated to load that meat cut. Referring to FIG. 16,when the machine vision stage identifies a yet larger meat cut M, allfive of the input conveyors are activated to load the meat cuts in to abag. The two or more conveyors need not necessarily be arranged in a“centered” configuration in which smaller meat cuts are delivered to thecenter conveyor. For example in an alternative configuration cuts can bealigned to one side with one, two, or more conveyors being activatedbased on the size of the cut. FIG. 17 shows conveyors to one sideactivated to load an intermediate size meat cut in a non-centeredsystem.

FIGS. 15 to 17 show five parallel conveyors including two conveyors oneither side which are of lesser width than a center conveyor.Alternatively, the conveyor system may comprise two conveyors havingsimilar widths or wherein one conveyor is wider than the other conveyor;three conveyors of similar widths or comprising a center conveyorflanked on either side by one or more other conveyors of lesser width,and so forth.

Referring back to FIG. 3, this as previously described shows onearrangement of a telescoping input conveyor system of the invention thatmay be used to load meat cuts M into open bags B. The forward end(s) ofthe one or more parallel load conveyor(s) (dependent on product size)may telescope into the bag which is presented to the meat cut, and thenwithdraw, depositing the meat cut within the bag, which is then carriedaway from the packing station on an exit conveyor. Operation of theinput conveyors is controlled such that where smaller meat cuts areconveyed by a single one of the input conveyors, the open mouth of thebag is aligned with that input conveyor, which telescopically depositsthe meat cut into the open bag. Where the meat cut and bag are larger,two or more of the input conveyors telescope together to deposit themeat cut into the open bag as described above, and the open bag ispositioned laterally relative to the direction of forward movement ofthe input conveyors so that the bag is aligned with the input conveyorsloading the meat cut. In one embodiment the conveyors are arranged todeliver products into the bags by telescoping or moving forward into thebags to an extent dependent upon the size of the product i.e. furtherfor longer products than for shorter products, based on product sizeinformation previously acquired at the upstream product informationacquisition stage.

FIGS. 18 and 19 show a conveyor system of the invention comprising fiveparallel conveyors. Referring to FIG. 18, any one or more of the lesserwidth conveyors 100 may be pivoted upwardly to the position of theconveyor indicated at U in FIG. 19, by mechanism 101 activated byoperating cylinder 103 which operates about the primary shaft 102 of theconveyor system. In this embodiment, where the meat cut and bag are ofmaximum size, all of the five conveyors may be in the lower positionindicated at L in FIG. 19 to convey the meat cut, into an open bag forexample. Where the meat cut is of lesser size, one or more of theconveyors 100 may be caused to pivot out of the way to the upperposition U so that the meat cut will be carried by a lesser number ofthe conveyors. A control system may control which combination ofconveyors is used i.e. which remains at position L and which pivots toposition U, dependent upon the size of the product, based on productsize information previously acquired at the upstream product informationacquisition stage.

The foregoing describes the invention including various embodimentsthereof.

1. A method for packing products comprising: a) at an upstream productinformation acquisition stage acquiring information relating to at leastone of the height, width, length, volume, shape, and weight ofindividual products on a product packing line; b) utilizing a machinefor supplying bags sequentially as individual products on a conveyorapproach a packing apparatus; c) automatedly taking up on an automatedbag opener a bag from the bag supply system as each individual productapproaches the bag opener, and machine opening a mouth of the bag to avariable extent of lift in a direction at approximately right angles toa major plane of the unopened bag, the degree of lift being steppedbetween a number of predetermined levels, and to a variable degree ofwidth opening in a direction approximately in a major plane of theunopened bag, the degree of width opening being stepped at fixed levels,based on information relating to at least one of the height, width,length, volume, shape, and weight of the product acquired at theupstream product information acquisition stage.
 2. The method of claim 1comprising moving the bag opener repeatedly between i) a position out ofthe product stream in which the bag opener takes up a bag from the bagsupply system; and ii) a position in the product stream for receiving aproduct in the bag after opening of the mouth thereof.
 3. The method ofclaim 1 comprising i) opening each bag by inserting one or more parts ofthe bag opener into the mouth of each bag; and ii) moving said one ormore parts to open the bag.
 4. The method of claim 1 comprising grippingthe bag from the exterior on either side of a major plane of the bag atthe mouth of the bag via suction grippers, to initially open the bag. 5.The method of claim 1 comprising making the bags on-line to a lengthtailored to the size of individual products by cutting and sealing bagsfrom tubular stock.